As shown in FIG. 1, a conventional liquid crystal display panel comprises: a first substrate 10 and a second substrate, wherein the first substrate 10 is, for example, a BOA (BM on Array, BM: black matrix) substrate, and the BOA substrate is made by forming a color filter film and a black matrix on an array substrate. The first substrate 10 comprises: a substrate 11, a first metal layer 12 formed on the substrate 11, which comprises a plurality of gate electrodes; a gate insulation layer 13 partially formed on the first metal layer 12 and used to separate the first metal layer 12 and an active layer 14; the active layer 14 partially formed on the gate insulation layer 13 and used to form a channel; a second metal layer 15 formed on the active layer 14, which comprises a plurality of source electrodes and drain electrodes; a second insulation layer 16 formed on the second metal layer 15 and used to separate the second metal layer 15 and a color resist layer 17; the color resist layer 17 formed on the second insulation layer 16, which comprises a plurality of color film resists (for example, red color films 171, green color films 172, and blue color films 173); a via 18 formed on the color resist layer 17; a black matrix layer formed on the color resist layer 17; and a transparent conductive layer 20 partially formed on the black matrix layer 191.
Because a reason of leveling property, it causes that the film thickness of the black matrix layer 191 on a display area to not be equal to the film thickness of the black matrix layer 192 on a periphery area. Moreover, the film thickness of the black matrix layer 192 on the periphery area is usually thicker, so that the contrast ratio thereof is worse.
When manufacturing the via, usually, first a through hole is drilled in a color resist layer; next a material of the black matrix is coated on the color resist layer having the through hole. Because a reason of leveling property, the thickness of the black matrix inside the through hole is thicker than the thickness of the black matrix which is on the outside of the through hole and formed above the color resist layer. For a later process, it is necessary to remove the black matrix inside the through hole by development. Since the thickness of the black matrix inside the through hole is thicker, the developing time is longer, and also the processing time is longer, so that the production cost is increased.
Hence, it is necessary to provide an array substrate and a manufacturing method thereof which solves the problems existing in the conventional technologies.